1. Field of the Invention
The present invention relates to an upper seat structure for a rear coil spring, and more particularly, the present invention relates to an upper seat structure for a rear coil spring, which supports an upper portion of the rear coil spring arranged on a rear axle for improving a function of a rear suspension.
2. Description of the Related Art
In a motor vehicle, a suspension serves to absorb vibration which is generated while the motor vehicle runs and thereby improve occupant's comfortableness upon being seated. Referring to FIG. 1, there is shown an upper seat for a rear coil spring, which supports an upper portion of the rear coil spring arranged on a rear axle of a motor vehicle.
As shown in FIG. 1, the upper seat 11 for the rear coil spring 13, which functions to support the upper portion of the rear coil spring 13 arranged on the rear axle (not shown), is provided on an inner side surface of each of a pair of side frame members 12 which are respectively positioned at both sides of the motor vehicle and extend in a lengthwise direction of the motor vehicle. The upper seat 11 possesses a plurality of bracket parts 14 which are formed along side and upper edges thereof. When the upper seat 11 is installed on the side frame member 12, the plurality of bracket parts 14 are welded to the side frame member 12.
However, the upper seat for the rear coil spring, constructed as mentioned above, suffers from defects as described below. That is to say, since the plurality of bracket parts are welded to the side frame member, when spring force of the rear coil spring acts in upward and downward directions, a moment is applied to the upper seat by load which is transferred from the rear coil spring, depending upon a distance between a load-exerting point and a securing point of the upper support. As a consequence, in the case that the load which is transferred from the rear coil spring to the upper seat, is substantial, that is, when a large moment is applied to the upper seat, the upper seat is deformed in a direction where the moment is applied thereto, whereby the plurality of bracket parts which are welded to the side frame member, are apt to be broken.